Confetti

Confetti is configuration provider for your Erlang applications.

Basically it's application:get_env/2 on steroids.

Features

Management console

Accessible via telnet - maintenance department will love you for this
Configuration reload in runtime (designated processes receive notifications on reload)
Easily extensible with your own management commands (plugins!)
(TODO) broadcast working configuration across the Erlang cluster

Configuration supervision

Increase your system's uptime - previous working configuration is DETS-cached in case someone messes up the configuration files
Broken config for process_a can not break process_b

Easy to use

application:start(confetti).

then

%% your process
%% (...)
init([]) ->
    confetti:use(my_foo),   %% reads configuration terms
                            %% from "conf/my_foo.conf",
                            %% spawns new configuration provider
                            %% if needed...

    confetti:fetch(my_foo),  %% fetches the configuration terms
    {ok, #state{}}.

%% (...)
%% react to configuration changes
handle_info({config_reloaded, NewConf}, State) -> (...)

Customizable

Write configuration validators and more:

confetti:use(foo, [
    %% Specify config file location
    {location, {"conf/bar", "foo.cnf"},

    %% Make sure it's more than just correct Erlang term
    %% or even transform the terms into something!
    %% Validator funs should accept Config and return {ok, NewConf}
    %% on success, error otherwise.
    {validators, [fun validate_foo_config/1]},

    %% ignore notifications for current process
    {subscribe, false}
]).

Expose any module via the management console:

-module(my_commands).
export([foo/1, foo/3]).

foo(help) ->
    "Foo does bar two times!".
foo(Param1, Param2, Param3) ->
    %% perform command logic
    "bar bar".

Let confetti know about it:

%% conf/mgmt_conf.conf
{port, 50000}.
{plugins, [my_commands]}.

Assuming your application is already running, perform live management configruation reload:

$ telnet localhost 50000

...

(nonode@nohost)> reload mgmt_conf
ok

Provide your own welcome screen to the management console, i.e.:

$ figlet MyApp > priv/helo.txt

Try it out quickly

Obtain the source code
rebar compile; erl -pa ebin -boot start_sasl -s confetti_app
1> example_srv:start_link().
telnet localhost 50000
Type help for available commands, and help COMMAND for command usage details.

License

BSD License. See LICENSE file for details.

Authors

Adam Rutkowski <adam.rutkowski@jtendo.com>

Contribute!

Feel encouraged to spot bugs/poor code and implement new sexy features.

Also, make sure, you add yourself to the authors where appropriate! Thanks.

jtendo/confetti